drivers/acpi/sleep.c

   1 /*
   2  * sleep.c - ACPI sleep support.
   3  *
   4  * Copyright (c) 2005 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
   5  * Copyright (c) 2004 David Shaohua Li <shaohua.li@intel.com>
   6  * Copyright (c) 2000-2003 Patrick Mochel
   7  * Copyright (c) 2003 Open Source Development Lab
   8  *
   9  * This file is released under the GPLv2.
  10  *
  11  */
  12
  13 #include <linux/delay.h>
  14 #include <linux/irq.h>
  15 #include <linux/dmi.h>
  16 #include <linux/device.h>
  17 #include <linux/suspend.h>
  18 #include <linux/reboot.h>
  19
  20 #include <asm/io.h>
  21
  22 #include <acpi/acpi_bus.h>
  23 #include <acpi/acpi_drivers.h>
  24
  25 #include "internal.h"
  26 #include "sleep.h"
  27
  28 u8 sleep_states[ACPI_S_STATE_COUNT];
  29
  30 static void acpi_sleep_tts_switch(u32 acpi_state)
  31 {
  32         union acpi_object in_arg = { ACPI_TYPE_INTEGER };
  33         struct acpi_object_list arg_list = { 1, &in_arg };
  34         acpi_status status = AE_OK;
  35
  36         in_arg.integer.value = acpi_state;
  37         status = acpi_evaluate_object(NULL, "\\_TTS", &arg_list, NULL);
  38         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
  39                 /*
  40                  * OS can't evaluate the _TTS object correctly. Some warning
  41                  * message will be printed. But it won't break anything.
  42                  */
  43                 printk(KERN_NOTICE "Failure in evaluating _TTS object\n");
  44         }
  45 }
  46
  47 static int tts_notify_reboot(struct notifier_block *this,
  48                         unsigned long code, void *x)
  49 {
  50         acpi_sleep_tts_switch(ACPI_STATE_S5);
  51         return NOTIFY_DONE;
  52 }
  53
  54 static struct notifier_block tts_notifier = {
  55         .notifier_call  = tts_notify_reboot,
  56         .next           = NULL,
  57         .priority       = 0,
  58 };
  59
  60 static int acpi_sleep_prepare(u32 acpi_state)
  61 {
  62 #ifdef CONFIG_ACPI_SLEEP
  63         /* do we have a wakeup address for S2 and S3? */
  64         if (acpi_state == ACPI_STATE_S3) {
  65                 if (!acpi_wakeup_address) {
  66                         return -EFAULT;
  67                 }
  68                 acpi_set_firmware_waking_vector(
  69                                 (acpi_physical_address)acpi_wakeup_address);
  70
  71         }
  72         ACPI_FLUSH_CPU_CACHE();
  73         acpi_enable_wakeup_device_prep(acpi_state);
  74 #endif
  75         printk(KERN_INFO PREFIX "Preparing to enter system sleep state S%d\n",
  76                 acpi_state);
  77         acpi_enter_sleep_state_prep(acpi_state);
  78         return 0;
  79 }
  80
  81 #ifdef CONFIG_ACPI_SLEEP
  82 static u32 acpi_target_sleep_state = ACPI_STATE_S0;
  83
  84 /*
  85  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
  86  * user to request that behavior by using the 'acpi_old_suspend_ordering'
  87  * kernel command line option that causes the following variable to be set.
  88  */
  89 static bool old_suspend_ordering;
  90
  91 void __init acpi_old_suspend_ordering(void)
  92 {
  93         old_suspend_ordering = true;
  94 }
  95
  96 /**
  97  * acpi_pm_freeze - Disable the GPEs and suspend EC transactions.
  98  */
  99 static int acpi_pm_freeze(void)
 100 {
 101         acpi_disable_all_gpes();
 102         acpi_os_wait_events_complete(NULL);
 103         acpi_ec_block_transactions();
 104         return 0;
 105 }
 106
 107 /**
 108  *      __acpi_pm_prepare - Prepare the platform to enter the target state.
 109  *
 110  *      If necessary, set the firmware waking vector and do arch-specific
 111  *      nastiness to get the wakeup code to the waking vector.
 112  */
 113 static int __acpi_pm_prepare(void)
 114 {
 115         int error = acpi_sleep_prepare(acpi_target_sleep_state);
 116
 117         suspend_nvs_save();
 118
 119         if (error)
 120                 acpi_target_sleep_state = ACPI_STATE_S0;
 121         return error;
 122 }
 123
 124 /**
 125  *      acpi_pm_prepare - Prepare the platform to enter the target sleep
 126  *              state and disable the GPEs.
 127  */
 128 static int acpi_pm_prepare(void)
 129 {
 130         int error = __acpi_pm_prepare();
 131
 132         if (!error)
 133                 acpi_pm_freeze();
 134
 135         return error;
 136 }
 137
 138 /**
 139  *      acpi_pm_finish - Instruct the platform to leave a sleep state.
 140  *
 141  *      This is called after we wake back up (or if entering the sleep state
 142  *      failed).
 143  */
 144 static void acpi_pm_finish(void)
 145 {
 146         u32 acpi_state = acpi_target_sleep_state;
 147
 148         suspend_nvs_free();
 149         acpi_ec_unblock_transactions();
 150
 151         if (acpi_state == ACPI_STATE_S0)
 152                 return;
 153
 154         printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
 155                 acpi_state);
 156         acpi_disable_wakeup_device(acpi_state);
 157         acpi_leave_sleep_state(acpi_state);
 158
 159         /* reset firmware waking vector */
 160         acpi_set_firmware_waking_vector((acpi_physical_address) 0);
 161
 162         acpi_target_sleep_state = ACPI_STATE_S0;
 163 }
 164
 165 /**
 166  *      acpi_pm_end - Finish up suspend sequence.
 167  */
 168 static void acpi_pm_end(void)
 169 {
 170         /*
 171          * This is necessary in case acpi_pm_finish() is not called during a
 172          * failing transition to a sleep state.
 173          */
 174         acpi_target_sleep_state = ACPI_STATE_S0;
 175         acpi_sleep_tts_switch(acpi_target_sleep_state);
 176 }
 177 #else /* !CONFIG_ACPI_SLEEP */
 178 #define acpi_target_sleep_state ACPI_STATE_S0
 179 #endif /* CONFIG_ACPI_SLEEP */
 180
 181 #ifdef CONFIG_SUSPEND
 182 extern void do_suspend_lowlevel(void);
 183
 184 static u32 acpi_suspend_states[] = {
 185         [PM_SUSPEND_ON] = ACPI_STATE_S0,
 186         [PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
 187         [PM_SUSPEND_MEM] = ACPI_STATE_S3,
 188         [PM_SUSPEND_MAX] = ACPI_STATE_S5
 189 };
 190
 191 /**
 192  *      acpi_suspend_begin - Set the target system sleep state to the state
 193  *              associated with given @pm_state, if supported.
 194  */
 195 static int acpi_suspend_begin(suspend_state_t pm_state)
 196 {
 197         u32 acpi_state = acpi_suspend_states[pm_state];
 198         int error = 0;
 199
 200         error = suspend_nvs_alloc();
 201
 202         if (error)
 203                 return error;
 204
 205         if (sleep_states[acpi_state]) {
 206                 acpi_target_sleep_state = acpi_state;
 207                 acpi_sleep_tts_switch(acpi_target_sleep_state);
 208         } else {
 209                 printk(KERN_ERR "ACPI does not support this state: %d\n",
 210                         pm_state);
 211                 error = -ENOSYS;
 212         }
 213         return error;
 214 }
 215
 216 /**
 217  *      acpi_suspend_enter - Actually enter a sleep state.
 218  *      @pm_state: ignored
 219  *
 220  *      Flush caches and go to sleep. For STR we have to call arch-specific
 221  *      assembly, which in turn call acpi_enter_sleep_state().
 222  *      It's unfortunate, but it works. Please fix if you're feeling frisky.
 223  */
 224 static int acpi_suspend_enter(suspend_state_t pm_state)
 225 {
 226         acpi_status status = AE_OK;
 227         unsigned long flags = 0;
 228         u32 acpi_state = acpi_target_sleep_state;
 229
 230         ACPI_FLUSH_CPU_CACHE();
 231
 232         /* Do arch specific saving of state. */
 233         if (acpi_state == ACPI_STATE_S3) {
 234                 int error = acpi_save_state_mem();
 235
 236                 if (error)
 237                         return error;
 238         }
 239
 240         local_irq_save(flags);
 241         acpi_enable_wakeup_device(acpi_state);
 242         switch (acpi_state) {
 243         case ACPI_STATE_S1:
 244                 barrier();
 245                 status = acpi_enter_sleep_state(acpi_state);
 246                 break;
 247
 248         case ACPI_STATE_S3:
 249                 do_suspend_lowlevel();
 250                 break;
 251         }
 252
 253         /* This violates the spec but is required for bug compatibility. */
 254         acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
 255
 256         /* Reprogram control registers and execute _BFS */
 257         acpi_leave_sleep_state_prep(acpi_state);
 258
 259         /* ACPI 3.0 specs (P62) says that it's the responsibility
 260          * of the OSPM to clear the status bit [ implying that the
 261          * POWER_BUTTON event should not reach userspace ]
 262          */
 263         if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
 264                 acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
 265
 266         /*
 267          * Disable and clear GPE status before interrupt is enabled. Some GPEs
 268          * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
 269          * acpi_leave_sleep_state will reenable specific GPEs later
 270          */
 271         acpi_disable_all_gpes();
 272         /* Allow EC transactions to happen. */
 273         acpi_ec_unblock_transactions_early();
 274
 275         local_irq_restore(flags);
 276         printk(KERN_DEBUG "Back to C!\n");
 277
 278         /* restore processor state */
 279         if (acpi_state == ACPI_STATE_S3)
 280                 acpi_restore_state_mem();
 281
 282         suspend_nvs_restore();
 283
 284         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 285 }
 286
 287 static void acpi_suspend_finish(void)
 288 {
 289         acpi_pm_finish();
 290 }
 291
 292 static int acpi_suspend_state_valid(suspend_state_t pm_state)
 293 {
 294         u32 acpi_state;
 295
 296         switch (pm_state) {
 297         case PM_SUSPEND_ON:
 298         case PM_SUSPEND_STANDBY:
 299         case PM_SUSPEND_MEM:
 300                 acpi_state = acpi_suspend_states[pm_state];
 301
 302                 return sleep_states[acpi_state];
 303         default:
 304                 return 0;
 305         }
 306 }
 307
 308 static struct platform_suspend_ops acpi_suspend_ops = {
 309         .valid = acpi_suspend_state_valid,
 310         .begin = acpi_suspend_begin,
 311         .prepare_late = acpi_pm_prepare,
 312         .enter = acpi_suspend_enter,
 313         .wake = acpi_suspend_finish,
 314         .end = acpi_pm_end,
 315 };
 316
 317 /**
 318  *      acpi_suspend_begin_old - Set the target system sleep state to the
 319  *              state associated with given @pm_state, if supported, and
 320  *              execute the _PTS control method.  This function is used if the
 321  *              pre-ACPI 2.0 suspend ordering has been requested.
 322  */
 323 static int acpi_suspend_begin_old(suspend_state_t pm_state)
 324 {
 325         int error = acpi_suspend_begin(pm_state);
 326
 327         if (!error)
 328                 error = __acpi_pm_prepare();
 329         return error;
 330 }
 331
 332 /*
 333  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 334  * been requested.
 335  */
 336 static struct platform_suspend_ops acpi_suspend_ops_old = {
 337         .valid = acpi_suspend_state_valid,
 338         .begin = acpi_suspend_begin_old,
 339         .prepare_late = acpi_pm_freeze,
 340         .enter = acpi_suspend_enter,
 341         .wake = acpi_suspend_finish,
 342         .end = acpi_pm_end,
 343         .recover = acpi_pm_finish,
 344 };
 345
 346 static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
 347 {
 348         old_suspend_ordering = true;
 349         return 0;
 350 }
 351
 352 static struct dmi_system_id __initdata acpisleep_dmi_table[] = {
 353         {
 354         .callback = init_old_suspend_ordering,
 355         .ident = "Abit KN9 (nForce4 variant)",
 356         .matches = {
 357                 DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
 358                 DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
 359                 },
 360         },
 361         {
 362         .callback = init_old_suspend_ordering,
 363         .ident = "HP xw4600 Workstation",
 364         .matches = {
 365                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 366                 DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
 367                 },
 368         },
 369         {
 370         .callback = init_old_suspend_ordering,
 371         .ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
 372         .matches = {
 373                 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTek Computer INC."),
 374                 DMI_MATCH(DMI_BOARD_NAME, "M2N8L"),
 375                 },
 376         },
 377         {
 378         .callback = init_old_suspend_ordering,
 379         .ident = "Panasonic CF51-2L",
 380         .matches = {
 381                 DMI_MATCH(DMI_BOARD_VENDOR,
 382                                 "Matsushita Electric Industrial Co.,Ltd."),
 383                 DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"),
 384                 },
 385         },
 386         {},
 387 };
 388 #endif /* CONFIG_SUSPEND */
 389
 390 #ifdef CONFIG_HIBERNATION
 391 /*
 392  * The ACPI specification wants us to save NVS memory regions during hibernation
 393  * and to restore them during the subsequent resume.  However, it is not certain
 394  * if this mechanism is going to work on all machines, so we allow the user to
 395  * disable this mechanism using the 'acpi_sleep=s4_nonvs' kernel command line
 396  * option.
 397  */
 398 static bool s4_no_nvs;
 399
 400 void __init acpi_s4_no_nvs(void)
 401 {
 402         s4_no_nvs = true;
 403 }
 404
 405 static unsigned long s4_hardware_signature;
 406 static struct acpi_table_facs *facs;
 407 static bool nosigcheck;
 408
 409 void __init acpi_no_s4_hw_signature(void)
 410 {
 411         nosigcheck = true;
 412 }
 413
 414 static int acpi_hibernation_begin(void)
 415 {
 416         int error;
 417
 418         error = s4_no_nvs ? 0 : suspend_nvs_alloc();
 419         if (!error) {
 420                 acpi_target_sleep_state = ACPI_STATE_S4;
 421                 acpi_sleep_tts_switch(acpi_target_sleep_state);
 422         }
 423
 424         return error;
 425 }
 426
 427 static int acpi_hibernation_pre_snapshot(void)
 428 {
 429         int error = acpi_pm_prepare();
 430
 431         if (!error)
 432                 suspend_nvs_save();
 433
 434         return error;
 435 }
 436
 437 static int acpi_hibernation_enter(void)
 438 {
 439         acpi_status status = AE_OK;
 440         unsigned long flags = 0;
 441
 442         ACPI_FLUSH_CPU_CACHE();
 443
 444         local_irq_save(flags);
 445         acpi_enable_wakeup_device(ACPI_STATE_S4);
 446         /* This shouldn't return.  If it returns, we have a problem */
 447         status = acpi_enter_sleep_state(ACPI_STATE_S4);
 448         /* Reprogram control registers and execute _BFS */
 449         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 450         local_irq_restore(flags);
 451
 452         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 453 }
 454
 455 static void acpi_hibernation_leave(void)
 456 {
 457         /*
 458          * If ACPI is not enabled by the BIOS and the boot kernel, we need to
 459          * enable it here.
 460          */
 461         acpi_enable();
 462         /* Reprogram control registers and execute _BFS */
 463         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 464         /* Check the hardware signature */
 465         if (facs && s4_hardware_signature != facs->hardware_signature) {
 466                 printk(KERN_EMERG "ACPI: Hardware changed while hibernated, "
 467                         "cannot resume!\n");
 468                 panic("ACPI S4 hardware signature mismatch");
 469         }
 470         /* Restore the NVS memory area */
 471         suspend_nvs_restore();
 472         /* Allow EC transactions to happen. */
 473         acpi_ec_unblock_transactions_early();
 474 }
 475
 476 static void acpi_pm_thaw(void)
 477 {
 478         acpi_ec_unblock_transactions();
 479         acpi_enable_all_runtime_gpes();
 480 }
 481
 482 static struct platform_hibernation_ops acpi_hibernation_ops = {
 483         .begin = acpi_hibernation_begin,
 484         .end = acpi_pm_end,
 485         .pre_snapshot = acpi_hibernation_pre_snapshot,
 486         .finish = acpi_pm_finish,
 487         .prepare = acpi_pm_prepare,
 488         .enter = acpi_hibernation_enter,
 489         .leave = acpi_hibernation_leave,
 490         .pre_restore = acpi_pm_freeze,
 491         .restore_cleanup = acpi_pm_thaw,
 492 };
 493
 494 /**
 495  *      acpi_hibernation_begin_old - Set the target system sleep state to
 496  *              ACPI_STATE_S4 and execute the _PTS control method.  This
 497  *              function is used if the pre-ACPI 2.0 suspend ordering has been
 498  *              requested.
 499  */
 500 static int acpi_hibernation_begin_old(void)
 501 {
 502         int error;
 503         /*
 504          * The _TTS object should always be evaluated before the _PTS object.
 505          * When the old_suspended_ordering is true, the _PTS object is
 506          * evaluated in the acpi_sleep_prepare.
 507          */
 508         acpi_sleep_tts_switch(ACPI_STATE_S4);
 509
 510         error = acpi_sleep_prepare(ACPI_STATE_S4);
 511
 512         if (!error) {
 513                 if (!s4_no_nvs)
 514                         error = suspend_nvs_alloc();
 515                 if (!error)
 516                         acpi_target_sleep_state = ACPI_STATE_S4;
 517         }
 518         return error;
 519 }
 520
 521 static int acpi_hibernation_pre_snapshot_old(void)
 522 {
 523         acpi_pm_freeze();
 524         suspend_nvs_save();
 525         return 0;
 526 }
 527
 528 /*
 529  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 530  * been requested.
 531  */
 532 static struct platform_hibernation_ops acpi_hibernation_ops_old = {
 533         .begin = acpi_hibernation_begin_old,
 534         .end = acpi_pm_end,
 535         .pre_snapshot = acpi_hibernation_pre_snapshot_old,
 536         .prepare = acpi_pm_freeze,
 537         .finish = acpi_pm_finish,
 538         .enter = acpi_hibernation_enter,
 539         .leave = acpi_hibernation_leave,
 540         .pre_restore = acpi_pm_freeze,
 541         .restore_cleanup = acpi_pm_thaw,
 542         .recover = acpi_pm_finish,
 543 };
 544 #endif /* CONFIG_HIBERNATION */
 545
 546 int acpi_suspend(u32 acpi_state)
 547 {
 548         suspend_state_t states[] = {
 549                 [1] = PM_SUSPEND_STANDBY,
 550                 [3] = PM_SUSPEND_MEM,
 551                 [5] = PM_SUSPEND_MAX
 552         };
 553
 554         if (acpi_state < 6 && states[acpi_state])
 555                 return pm_suspend(states[acpi_state]);
 556         if (acpi_state == 4)
 557                 return hibernate();
 558         return -EINVAL;
 559 }
 560
 561 #ifdef CONFIG_PM_SLEEP
 562 /**
 563  *      acpi_pm_device_sleep_state - return preferred power state of ACPI device
 564  *              in the system sleep state given by %acpi_target_sleep_state
 565  *      @dev: device to examine; its driver model wakeup flags control
 566  *              whether it should be able to wake up the system
 567  *      @d_min_p: used to store the upper limit of allowed states range
 568  *      Return value: preferred power state of the device on success, -ENODEV on
 569  *              failure (ie. if there's no 'struct acpi_device' for @dev)
 570  *
 571  *      Find the lowest power (highest number) ACPI device power state that
 572  *      device @dev can be in while the system is in the sleep state represented
 573  *      by %acpi_target_sleep_state.  If @wake is nonzero, the device should be
 574  *      able to wake up the system from this sleep state.  If @d_min_p is set,
 575  *      the highest power (lowest number) device power state of @dev allowed
 576  *      in this system sleep state is stored at the location pointed to by it.
 577  *
 578  *      The caller must ensure that @dev is valid before using this function.
 579  *      The caller is also responsible for figuring out if the device is
 580  *      supposed to be able to wake up the system and passing this information
 581  *      via @wake.
 582  */
 583
 584 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p)
 585 {
 586         acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
 587         struct acpi_device *adev;
 588         char acpi_method[] = "_SxD";
 589         unsigned long long d_min, d_max;
 590
 591         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
 592                 printk(KERN_DEBUG "ACPI handle has no context!\n");
 593                 return -ENODEV;
 594         }
 595
 596         acpi_method[2] = '0' + acpi_target_sleep_state;
 597         /*
 598          * If the sleep state is S0, we will return D3, but if the device has
 599          * _S0W, we will use the value from _S0W
 600          */
 601         d_min = ACPI_STATE_D0;
 602         d_max = ACPI_STATE_D3;
 603
 604         /*
 605          * If present, _SxD methods return the minimum D-state (highest power
 606          * state) we can use for the corresponding S-states.  Otherwise, the
 607          * minimum D-state is D0 (ACPI 3.x).
 608          *
 609          * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
 610          * provided -- that's our fault recovery, we ignore retval.
 611          */
 612         if (acpi_target_sleep_state > ACPI_STATE_S0)
 613                 acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);
 614
 615         /*
 616          * If _PRW says we can wake up the system from the target sleep state,
 617          * the D-state returned by _SxD is sufficient for that (we assume a
 618          * wakeup-aware driver if wake is set).  Still, if _SxW exists
 619          * (ACPI 3.x), it should return the maximum (lowest power) D-state that
 620          * can wake the system.  _S0W may be valid, too.
 621          */
 622         if (acpi_target_sleep_state == ACPI_STATE_S0 ||
 623             (device_may_wakeup(dev) && adev->wakeup.state.enabled &&
 624              adev->wakeup.sleep_state <= acpi_target_sleep_state)) {
 625                 acpi_status status;
 626
 627                 acpi_method[3] = 'W';
 628                 status = acpi_evaluate_integer(handle, acpi_method, NULL,
 629                                                 &d_max);
 630                 if (ACPI_FAILURE(status)) {
 631                         d_max = d_min;
 632                 } else if (d_max < d_min) {
 633                         /* Warn the user of the broken DSDT */
 634                         printk(KERN_WARNING "ACPI: Wrong value from %s\n",
 635                                 acpi_method);
 636                         /* Sanitize it */
 637                         d_min = d_max;
 638                 }
 639         }
 640
 641         if (d_min_p)
 642                 *d_min_p = d_min;
 643         return d_max;
 644 }
 645
 646 /**
 647  *      acpi_pm_device_sleep_wake - enable or disable the system wake-up
 648  *                                  capability of given device
 649  *      @dev: device to handle
 650  *      @enable: 'true' - enable, 'false' - disable the wake-up capability
 651  */
 652 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
 653 {
 654         acpi_handle handle;
 655         struct acpi_device *adev;
 656         int error;
 657
 658         if (!device_can_wakeup(dev))
 659                 return -EINVAL;
 660
 661         handle = DEVICE_ACPI_HANDLE(dev);
 662         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
 663                 dev_dbg(dev, "ACPI handle has no context in %s!\n", __func__);
 664                 return -ENODEV;
 665         }
 666
 667         if (enable) {
 668                 error = acpi_enable_wakeup_device_power(adev,
 669                                                 acpi_target_sleep_state);
 670                 if (!error)
 671                         acpi_enable_gpe(adev->wakeup.gpe_device,
 672                                         adev->wakeup.gpe_number,
 673                                         ACPI_GPE_TYPE_WAKE);
 674         } else {
 675                 acpi_disable_gpe(adev->wakeup.gpe_device, adev->wakeup.gpe_number,
 676                                 ACPI_GPE_TYPE_WAKE);
 677                 error = acpi_disable_wakeup_device_power(adev);
 678         }
 679         if (!error)
 680                 dev_info(dev, "wake-up capability %s by ACPI\n",
 681                                 enable ? "enabled" : "disabled");
 682
 683         return error;
 684 }
 685 #endif
 686
 687 static void acpi_power_off_prepare(void)
 688 {
 689         /* Prepare to power off the system */
 690         acpi_sleep_prepare(ACPI_STATE_S5);
 691         acpi_disable_all_gpes();
 692 }
 693
 694 static void acpi_power_off(void)
 695 {
 696         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
 697         printk(KERN_DEBUG "%s called\n", __func__);
 698         local_irq_disable();
 699         acpi_enable_wakeup_device(ACPI_STATE_S5);
 700         acpi_enter_sleep_state(ACPI_STATE_S5);
 701 }
 702
 703 /*
 704  * ACPI 2.0 created the optional _GTS and _BFS,
 705  * but industry adoption has been neither rapid nor broad.
 706  *
 707  * Linux gets into trouble when it executes poorly validated
 708  * paths through the BIOS, so disable _GTS and _BFS by default,
 709  * but do speak up and offer the option to enable them.
 710  */
 711 void __init acpi_gts_bfs_check(void)
 712 {
 713         acpi_handle dummy;
 714
 715         if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__GTS, &dummy)))
 716         {
 717                 printk(KERN_NOTICE PREFIX "BIOS offers _GTS\n");
 718                 printk(KERN_NOTICE PREFIX "If \"acpi.gts=1\" improves suspend, "
 719                         "please notify linux-acpi@vger.kernel.org\n");
 720         }
 721         if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__BFS, &dummy)))
 722         {
 723                 printk(KERN_NOTICE PREFIX "BIOS offers _BFS\n");
 724                 printk(KERN_NOTICE PREFIX "If \"acpi.bfs=1\" improves resume, "
 725                         "please notify linux-acpi@vger.kernel.org\n");
 726         }
 727 }
 728
 729 int __init acpi_sleep_init(void)
 730 {
 731         acpi_status status;
 732         u8 type_a, type_b;
 733 #ifdef CONFIG_SUSPEND
 734         int i = 0;
 735
 736         dmi_check_system(acpisleep_dmi_table);
 737 #endif
 738
 739         if (acpi_disabled)
 740                 return 0;
 741
 742         sleep_states[ACPI_STATE_S0] = 1;
 743         printk(KERN_INFO PREFIX "(supports S0");
 744
 745 #ifdef CONFIG_SUSPEND
 746         for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
 747                 status = acpi_get_sleep_type_data(i, &type_a, &type_b);
 748                 if (ACPI_SUCCESS(status)) {
 749                         sleep_states[i] = 1;
 750                         printk(" S%d", i);
 751                 }
 752         }
 753
 754         suspend_set_ops(old_suspend_ordering ?
 755                 &acpi_suspend_ops_old : &acpi_suspend_ops);
 756 #endif
 757
 758 #ifdef CONFIG_HIBERNATION
 759         status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
 760         if (ACPI_SUCCESS(status)) {
 761                 hibernation_set_ops(old_suspend_ordering ?
 762                         &acpi_hibernation_ops_old : &acpi_hibernation_ops);
 763                 sleep_states[ACPI_STATE_S4] = 1;
 764                 printk(" S4");
 765                 if (!nosigcheck) {
 766                         acpi_get_table(ACPI_SIG_FACS, 1,
 767                                 (struct acpi_table_header **)&facs);
 768                         if (facs)
 769                                 s4_hardware_signature =
 770                                         facs->hardware_signature;
 771                 }
 772         }
 773 #endif
 774         status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
 775         if (ACPI_SUCCESS(status)) {
 776                 sleep_states[ACPI_STATE_S5] = 1;
 777                 printk(" S5");
 778                 pm_power_off_prepare = acpi_power_off_prepare;
 779                 pm_power_off = acpi_power_off;
 780         }
 781         printk(")\n");
 782         /*
 783          * Register the tts_notifier to reboot notifier list so that the _TTS
 784          * object can also be evaluated when the system enters S5.
 785          */
 786         register_reboot_notifier(&tts_notifier);
 787         acpi_gts_bfs_check();
 788         return 0;
 789 }